FIXME: experimental imgui fixes

Author: notimaginative

code/def_files/data/fonts/BankGothic-BT-Light.ttf

@@ -282,6 +282,9 @@ namespace os
 		 * @note Implementation may ignore invocations of this function
 		 */
 		virtual void restore() = 0;
+
+		virtual float getCoordScale() { return 1.0f; }
+		virtual float getScaled(float val) { return val; }
 	};
 
 	/**

code/osapi/osapi.h

@@ -280,6 +280,10 @@ add_file_folder("Default files\\\\data\\\\effects"
 	def_files/data/effects/volumetric-f.sdr
 )
 
+add_file_folder("Default files\\\\data\\\\fonts"
+	def_files/data/fonts/BankGothic-BT-Light.ttf
+)
+
 add_file_folder("Default files\\\\data\\\\maps"
 	def_files/data/maps/app_icon.png
 	def_files/data/maps/app_icon_d.png
@@ -315,6 +319,7 @@ add_file_folder("Default files\\\\builtin"
 set(default_files_files
 	${files_Default_files_data}
 	${files_Default_files_data_effects}
+	${files_Default_files_data_fonts}
 	${files_Default_files_data_maps}
 	${files_Default_files_data_scripts}
 	${files_Default_files_data_tables}

code/source_groups.cmake

@@ -85,6 +85,24 @@ class SDLWindowViewPort: public os::Viewport {
  public:
 	SDLWindowViewPort(SDL_Window* window, const os::ViewPortProperties& props) : _window(window), _props(props) {
 		Assertion(window != nullptr, "Invalid window specified");
+
+		// scaling for high dpi stuff
+		{
+			int window_w, window_h;
+			int framebuffer_w, framebuffer_h;
+
+			SDL_GetWindowSize(window, &window_w, &window_h);
+			SDL_GetWindowSizeInPixels(window, &framebuffer_w, &framebuffer_h);
+
+			float sx = framebuffer_w / static_cast<float>(window_w);
+			float sy = framebuffer_h / static_cast<float>(window_h);
+
+			m_coord_scale = std::max(sx, sy);
+			m_content_scale = SDL_GetWindowDisplayScale(window);
+			m_scale_factor = m_content_scale / m_coord_scale;
+
+			ImGui::GetStyle().ScaleAllSizes(m_scale_factor);
+		}
 	}
 	~SDLWindowViewPort() override {
 		SDL_DestroyWindow(_window);
@@ -136,6 +154,13 @@ class SDLWindowViewPort: public os::Viewport {
 	void restore() override {
 		SDL_RestoreWindow(_window);
 	}
+
+	float m_coord_scale;
+	float m_content_scale;
+	float m_scale_factor;
+
+	float getCoordScale() override { return m_coord_scale; }
+	float getScaled(float val) override { return val * m_scale_factor; }
 };
 
 SDLGraphicsOperations::SDLGraphicsOperations() {

freespace2/SDLGraphicsOperations.cpp

@@ -1820,6 +1820,8 @@ void game_init()
 	Random::seed(static_cast<unsigned int>(time(nullptr)));
 
 	ImGui::CreateContext();
+	ImGui::GetIO().IniFilename = nullptr;
+	ImGui::LoadIniSettingsFromDisk(os_get_config_path("imgui.ini").c_str());
 
 	Framerate_delay = 0;
 
@@ -1968,6 +1970,31 @@ void game_init()
 		return;
 	}
 
+	if ( !Is_standalone ) {
+		ImGuiIO &io = ImGui::GetIO(); (void)io;
+
+		io.Fonts->Clear();
+		ImFontConfig fontConfig;
+
+		fontConfig.RasterizerDensity = os::getMainViewport()->getCoordScale();;
+
+		auto file = cfopen("BankGothic-BT-Light.ttf", "rb", CF_TYPE_FONT);
+
+		if (file) {
+			const auto size = cfilelength(file);
+
+			// NOTE: ImGui will free this memory on shutdown
+			uint8_t *font = reinterpret_cast<uint8_t*>(IM_ALLOC(size * (sizeof(uint8_t))));
+
+			cfread(font, 1, size, file);
+
+			cfclose(file);
+			file = nullptr;
+
+			io.Fonts->AddFontFromMemoryTTF(font, size, os::getMainViewport()->getScaled(12.f), &fontConfig);
+		}
+	}
+
 	if (LoggingEnabled && Cmdline_debug_window) {
 		outwnd_debug_window_init();
 	}
@@ -7000,6 +7027,11 @@ int game_main(int argc, char *argv[])
 			break;
 		}
 
+		if (ImGui::GetIO().WantSaveIniSettings) {
+			ImGui::SaveIniSettingsToDisk(os_get_config_path("imgui.ini").c_str());
+			ImGui::GetIO().WantSaveIniSettings = false;
+		}
+
 		// Since tracing is always active this needs to happen in the main loop
 		tracing::process_events();
 	} 
@@ -7110,6 +7142,7 @@ void game_shutdown(void)
 		std_deinit_standalone();
 	}
 
+	ImGui::SaveIniSettingsToDisk(os_get_config_path("imgui.ini").c_str());
 	ImGui::DestroyContext();
 
 	os_cleanup();